1. Field of Application
In its more general aspect, the present invention relates to an electronic device of the type comprising a die of semiconductor material having a plurality of contact pads connected, e.g., through contact wires, to a support or an integrated circuit having electrically conductive areas or regions.
In particular, the present invention relates to a semiconductor device as above that can incorporate a higher number of functions while maintaining the same size for the die of semiconductor material or have a smaller die of semiconductor material with the same number of functions therein incorporated.
The present invention also relates to a method for manufacturing a semiconductor electronic device of the above type.
2. Description of the Related Art
As it is well known, the semiconductor electronic devices, such as power devices, comprise a die of semiconductor material, the so-called die, is a few square millimeter area whereon an electronic circuit is monolithically integrated. The die has a plurality of terminals, typically contact pads (the so-called pads) superficially formed and electrically interconnected with a support, the so-called lead frame, also being part of the electronic device.
The electrical connection between the die of semiconductor material and the support can be realized through different technologies, among which the most employed provides the use of contact wires and is therefore known as wire bonding. More particularly, each contact wire is welded at an end on a contact pad formed on the die of semiconductor material and, at the opposite end, on a corresponding contact pad formed on the support whereto the die has to be connected.
The contact pads, generally numbering in the hundreds, are arranged on the surface of the die of semiconductor material and along the boundary thereof. They can be substantially arranged according to two typologies: linear and staggered.
In the linear disposition, the contact pads are arranged in a single chain along the sides of the die of semiconductor material. In such a way, however, it is possible to arrange only a limited number of contact pads, otherwise sizes and costs for manufacturing the die of semiconductor material would be increased.
Instead, in the staggered arrangement, each side of the die of semiconductor material has two contact pad chains that are staggered relative to each other. The staggered arrangement has thus the advantage of making the die of semiconductor material more compact.
Generally, the contact pads arranged on a die of semiconductor material have a multilayer structure comprising metallic material layers (generally aluminum or copper) alternated by insulating material layers. Of these layers, the upper terminal or more external layer, which is of metallic material, is used for connection with the contact wires and one of the metallic layers is in communication with the circuit components of the die of semiconductor material. Moreover the metallic layers of the contact pads are in communication with each other through contact holes.
In the field of the design of integrated circuits, it is known the use of dies of semiconductor material whereon contact pads are implemented, these pads being connected with blocks integrating signal functions (later on simply indicated as signal pads) and distinct contact pads connected with blocks integrating power functions (later on simply indicated as power pads).
In this technical field, it is also known the more and more compelling need of reducing the size of the dies of semiconductor material without reducing the number of functions implemented thereon, in order to reach a reduction of the manufacturing costs and more compact electronic devices. Another need, which is strictly related to the one above, is instead that of increasing the number of functions in the dies of semiconductor material without increasing their size in order to have more efficient semiconductor electronic devices being at the same time fairly compact.
There remains a need in the art to provide a semiconductor electronic device having such structural and functional characteristics as to satisfy the above needs.